2 Answers
2

Not on my Iphone 4 iOS 4.1. Maybe this is a setting managed by the exchange administrator? Also the "No Limit" is missing from my list of options.
–
EspoSep 10 '10 at 6:46

1

That's correct. Your Exchange admin can control those settings, so it's possible you're simply not allowed for security reasons or resource management. I'm running an account on an Exchange mailbox and I have all the options available.
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pauldunlopSep 10 '10 at 11:04

The reason for this is that the Exchange Administrator has used the iPhone Configuration Utility on the server to adjust how many weeks of mail you are allowed to sync. It is not possible to override this value on the phone itself without jailbraking.